A NOTE ON GENERALIZED RIDGE ESTIMATORS

It is shown that a necessary and sufficient condition derived by Farebrother (1984) for a generalized ridge estimator to dominate the ordinary least-squares estimator with respect to the mean-square-error-matrix criterion in the linear regression model admits a similar interpretation as the well known criterion of Toro-Viz-carrondo and Wallace (1968) for the dominance of a restricted least-squares estimator over the ordinary least-squares estimator. Two other properties of the generalized ridge estimators, referring to the concept of admissibility, are also pointed out. © 1990, Taylor & Francis Group, LLC. All rights reserved.